Single versus bilateral lung transplantation for idiopathic pulmonary fibrosis

Elderly lung transplant recipients show acceptable long-term outcomes for lung transplantation: A propensity score-matched analysis

PURPOSE

Although the performance lung transplantation (LTx) in the elderly (≥ 60 years) has increased globally, the situation in Japan remains quite different, because the age limit at registration for cadaveric transplantation is 60 years. We investigated the long-term outcomes of LTx in the elderly in Japan.

METHODS

This was a single-center retrospective study. We divided the patients into two groups according to age: the younger group (< 60 years; Y group; n = 194) and the elderly group (≥ 60 years; E group; n = 10). We performed three-to-one propensity score matching to compare the long-term survival between the E and Y groups.

RESULTS

In the E group, the survival rate was significantly worse (p = 0.003), and single-LTx was more frequent (p = 0.036). There was a significant difference in the indications for LTx between the two groups (p < 0.001). The 5-year survival rate after single-LTx in the E group was significantly lower than that in the Y group (p = 0.006). After propensity score matching, the 5-year survival rates of the two groups were comparable (p = 0.55). However, the 5-year survival rate after single-LTx in the E group was significantly lower than that in the Y group (p = 0.007).

CONCLUSION

Elderly patients showed acceptable long-term survival after LTx.

Trends and Outcomes in Lung Transplantation in Patients with and without Idiopathic Pulmonary Fibrosis in Spain during the Period 2016-2020

(1) Background: This paper aims to assess temporal trends (2016-2020) in incidence, patient's characteristics, complications, length of hospital stay (LOHS) and in-hospital mortality (IHM) among patients with and without idiopathic pulmonary fibrosis (IPF) undergoing lung transplantation (LTx). We also analyse the effect of the COVID-19 pandemic on LTx in these populations. (2) Methods: A retrospective, population-based observational study was conducted using the Spanish National Hospital Discharge Database. Multivariable adjustment was conducted with logistic regression to analyse the IHM. (3) Results: We identified 1777 admissions for LTx during the study period, of which 573 (32.2%) were performed in patients with IPF. The number of hospital admissions for LTx rose from 2016 to 2020, both in patients with and without IPF, but a marked reduction was observed from year 2019 to year 2020. Over time, the proportion of single LTx decreased and bilateral LTx increased significantly in both groups. The incidence of LTx complications increased significantly over time along with the increase in the incidence of IPF. No significant differences in the incidence of complications or in the IHM between patients with and without IPF were found. Suffering any complication of the LTx and pulmonary hypertension were conditions positively associated with IHM in patients with and without IPF. The IHM remained stable from 2016 to 2020 in both study populations and was not affected by the COVID pandemic. (4) Conclusions: Patients with IPF account for almost a third of all lung transplants. The number of LTx increased over time in patients with and without IPF, but a marked reduction was observed from 2019 to 2020. Although the proportion of LTx complications increased significantly over time in both groups, the IHM did not change. IPF was not associated with increased complications or IHM after LTx.

Lung transplantation for interstitial lung disease: evolution over three decades

BACKGROUND

Interstitial lung disease (ILD) has emerged as the most common indication for lung transplantation globally. However, post-transplant survival varies depending on the underlying disease phenotype and comorbidities. This study aimed to describe the demographics, disease classification, outcomes and factors associated with post-transplant survival in a large single-centre cohort.

METHODS

Data were retrospectively assessed for 284 recipients who underwent lung transplantation for ILD in our centre between 1987 and 2020. Patient characteristics and outcomes were stratified by three eras: 1987-2000, 2001-2010 and 2011-2020.

RESULTS

Median patients' age at time of transplantation was significantly higher in the most recent decade (56 (51-61) years, p<0.0001). Recipients aged over 50 years had worse overall survival compared with younger patients (adjusted HR, aHR 2.36, 95% CI 1.55 to 3.72, p=0.0001). Better survival was seen with bilateral versus single lung transplantation in patients younger than 50 years (log-rank p=0.0195). However, this survival benefit was no longer present in patients aged over 50 years. Reduced survival was observed in fibrotic non-specific interstitial pneumonia compared with idiopathic pulmonary fibrosis, which remained the most common indication throughout (aHR 2.61, 95% CI 1.40 to 4.60, p=0.0015).

CONCLUSION

In patients transplanted for end-stage ILD, older age and fibrotic non-specific interstitial pneumonia were associated with poorer post-transplant survival. The benefit of bilateral over single lung transplantation diminished with increasing age, suggesting that single lung transplantation might still be a feasible option in older candidates.

Association of cardiac disease with the risk of post-lung transplantation mortality in Chinese recipients aged over 65 years

The current organ allocation rules prioritize elderly and urgent patients on the lung transplantation (LT) waiting list. A steady increase in the threshold at which age is taken into consideration for LT has been observed. This retrospective cohort study recruited 166 lung transplant recipients aged ≽ 65 years between January 2016 and October 2020 in the largest LT center in China. In the cohort, subgroups of patients aged 65-70 years (111 recipients, group 65-70) and ≽ 70 years (55 recipients, group ≽ 70) were included. Group D restrictive lung disease was the main indication of a lung transplant in recipients over 65 years. A significantly higher percentage of coronary artery stenosis was observed in the group ≽ 70 (30.9% vs. 14.4% in group 65-70, P = 0.014). ECMO bridging to LT was performed in 5.4% (group 65-70) and 7.3% (group ≽ 70) of patients. Kaplan-Meier estimates showed that recipients with cardiac abnormalities had a significantly increased risk of mortality. After adjusting for potential confounders, cardiac abnormality was shown to be independently associated with the increased risk of post-LT mortality (HR 6.37, P = 0.0060). Our result showed that LT can be performed in candidates with an advanced age and can provide life-extending benefits.

Health-Related Quality of Life Outcomes Following Single or Bilateral Lung Transplantation: A Systematic Review

BACKGROUND

Lung transplantation is the definitive treatment for end-stage lung disease. There has been uncertainty regarding whether single or bilateral lung transplantation confers patients' greater health-related quality of life. This systematic review was performed to evaluate the impact of single lung transplantation (SLTx) against bilateral lung transplantation on short- and long-term health-related quality of life.

METHODS

A literature search was conducted on PubMed for studies matching the eligibility criteria between January 2000 and January 2022. OVID (MEDLINE), Google Scholar, EBSCOhost (EMBASE), and bibliographies of included studies were reviewed. Inclusion of studies was based on predetermined eligibility criteria. Quality appraisal and data tabulation were performed using predetermined forms. Results were synthesized by narrative review. The structure of this systematic review follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. This systematic review was prospectively registered in the PROSPERO register (CRD42022344389).

RESULTS

Ten studies (1916 patients) were included. Within 12 mo posttransplantation, there was no evidence of the improved health-related quality of life with respect to the type of lung transplantation procedure. Bilateral lung transplantation patients reported significantly greater scores in both the physical and mental health domains of health-related quality of life. Bilateral lung transplantation offered significantly better health-related quality of life outcomes at later follow-up periods. Bilateral lung transplantation showed a significantly slower reduction in health-related quality of life physical composite scores relative to SLTx.

CONCLUSION

Bilateral lung transplant (BLTx) recipients perceive the greater health-related quality of life beyond 1-y post-lung transplantation. BLTx recipients better retain their health-related quality of life long-term posttransplantation than those receiving SLTx.

Right Heart Echocardiography Parameters and Other Predictors to Evaluate Mechanical Cardiac Support Necessity During Lung Transplantation

BACKGROUND

Lung transplantation (LuTx) is a challenge when right heart function fails. Mechanical circulatory support (MCS) is then necessary.

METHODS

We aimed to investigate whether preoperative transthoracic echocardiography (TTE) can predict MCS use and help to exclude the sickest patients. Between 2011 and 2018, 52 patients at our institution received LuTx and qualified for this study: 35 bilateral, 16 single, 1 lobar [1] and 1 retransplantation procedure. Of these, 22 were operated using MCS and 30 without MCS. The patients were aged between 18 and 65 years, and 23 were women. The indications were lung fibrosis for 18 patients, chronic obstructive lung disease for 16, cystic fibrosis for 15, primary pulmonary hypertension for 2 and bronchiectasis for 1. TTE was performed up to 30 days before treatment and 1 to 7 days after.

RESULTS

Patients undergoing MCS versus patients not undergoing MCS: preoperative right ventricular systolic pressure 56.5 (30) vs 37.8 (11.5) mm Hg (P = .03); tricuspid regurgitation pressure gradient 48.7 (27) vs 30.2 (10.8) mm Hg (P = .015); tricuspid annular plane systolic excursion 17.8 (4.3) vs 19.9 (2.8) mm Hg (P = .04); pulmonary artery diameter 27.5 (5.2) vs 23.9 (4.1) mm (P = .004); age 41.9 (14.1) vs 54.3 (11.8) years (P = .001). Patients who were Dead versus patients who were alive pulmonary valve acceleration time of 82.8 (24.1) vs 104.9 (27.2) ms (hazard ratio [HR] = 0.959, 95% confidence interval [CI] = 0.923-0.996 per ms, P = .02) and pulmonary artery diameter of 28.9 (5.8) vs 24.4 (4.1) mm HR = 1.225, 95% CI = 1.028-1.460 per 1 mm, P = .016 were predictors of death.

CONCLUSIONS

Preoperative TTE parameters: right ventricular systolic pressure, tricuspid regurgitation pressure gradient, tricuspid annular plane systolic excursion, and pulmonary artery diameter predicted MCS use during LuTx. Certain values of valve acceleration time and pulmonary artery diameter could help discern LuTx qualification.

Role of Mesenchymal Stem Cells and Extracellular Vesicles in Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a progressive interstitial fibrotic disease that leads to disability and death within 5 years of diagnosis. Pulmonary fibrosis is a disease with a multifactorial etiology. The concept of aberrant regeneration of the pulmonary epithelium reveals the pathogenesis of IPF, according to which repeated damage and death of alveolar epithelial cells is the main mechanism leading to the development of progressive IPF. Cell death provokes the migration, proliferation and activation of fibroblasts, which overproduce extracellular matrix, resulting in fibrotic deformity of the lung tissue. Mesenchymal stem cells (MSCs) and extracellular vesicles (EVs) are promising therapies for pulmonary fibrosis. MSCs, and EVs derived from MSCs, modulate the activity of immune cells, inhibit the expression of profibrotic genes, reduce collagen deposition and promote the repair of damaged lung tissue. This review considers the molecular mechanisms of the development of IPF and the multifaceted role of MSCs in the therapy of IPF. Currently, EVs-MSCs are regarded as a promising cell-free therapy tool, so in this review we discuss the results available to date of the use of EVs-MSCs for lung tissue repair.

Lung Transplant Type & Donor Age in Idiopathic Pulmonary Fibrosis: A Single Center Study

BACKGROUD

Idiopathic pulmonary fibrosis (IPF) accounts for a marked proportion of diagnoses on the US lung transplant (LTx) list. The effects of single (SLT) versus double LTx (DLT) and lung donor age on survival in IPF remain unclear and were investigated in this study.

METHODS

We retrospectively assessed survival of LTx recipients with IPF at a single institution from February 2012-March 2020. Survival was analyzed and compared between LTx types (SLT and DLT), donor ages, and the combined groups (LTx type & donor age) using Kaplan-Meier survival analysis and compared by log-rank test. P-values less than 0.05 were considered significant.

RESULTS

Of 744 LTx patients at our institution, 307 (41.3%) were diagnosed with IPF, of which 208 (67.8%) were SLT, and 97 (31.6%) were DLT (2 excluded patients underwent heart-lung transplantation). There was no significant difference in survival due to LTx type (P = 0.41) or for patients with donor age <50 or ≥50 y (P = 0.46). Once stratified by both LTx type and donor age, analysis showed no significant difference in survival between the four groups (P = 0.69).

CONCLUSIONS

With ethical consideration for organ allocation, as the average age of the US population increases, donor lungs aged ≥50 are an increasingly useful resource in LTx. Our findings suggest donor age and LTx type do not significantly affect survival. Therefore, SLT, and donor lungs aged ≥50 ought to be more readily considered as non-inferior options for LTx in patients with IPF.

Antifibrotic drugs in lung transplantation and chronic lung allograft dysfunction: a review

This review aims to provide an overview of pre-transplant antifibrotic therapy on peri-transplant outcomes and to address the possible role of antifibrotics in lung transplant recipients with chronic lung allograft dysfunction.Lung transplantation is an established treatment modality for patients with various end-stage lung diseases, of which idiopathic pulmonary fibrosis and other progressive fibrosing interstitial lung diseases are growing indications. Theoretically, widespread use of antifibrotics prior to lung transplantation may increase the risk of bronchial anastomotic complications and impaired wound healing.Long-term graft and patient survival are still hampered by development of chronic lung allograft dysfunction, on which antifibrotics may have a beneficial impact.Antifibrotics until the moment of lung transplantation proved to be safe, without increasing peri-transplant complications. Currently, best practice is to continue antifibrotics until time of transplantation. In a large multicentre randomised trial, pirfenidone did not appear to have a beneficial effect on lung function decline in established bronchiolitis obliterans syndrome. The results of antifibrotic therapy in restrictive allograft syndrome are eagerly awaited, but nonrandomised data from small case reports/series are promising.

Idiopathic pulmonary fibrosis: Molecular mechanisms and potential treatment approaches

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive disease with high mortality that commonly occurs in middle-aged and older adults. IPF, characterized by a decline in lung function, often manifests as exertional dyspnea and cough. Symptoms result from a fibrotic process driven by alveolar epithelial cells that leads to increased migration, proliferation, and differentiation of lung fibroblasts. Ultimately, the differentiation of fibroblasts into myofibroblasts, which synthesize excessive amounts of extracellular matrix proteins, destroys the lung architecture. However, the factors that induce the fibrotic process are unclear. Diagnosis can be a difficult process; the gold standard for diagnosis is the multidisciplinary conference. Practical biomarkers are needed to improve diagnostic and prognostic accuracy. High-resolution computed tomography typically shows interstitial pneumonia with basal and peripheral honeycombing. Gas exchange and diffusion capacity are impaired. Treatments are limited, although the anti-fibrotic drugs pirfenidone and nintedanib can slow the progression of the disease. Lung transplantation is often contraindicated because of age and comorbidities, but it improves survival when successful. The incidence and prevalence of IPF has been increasing and there is an urgent need for improved therapies. This review covers the detailed cellular and molecular mechanisms underlying IPF progression as well as current treatments and cutting-edge research into new therapeutic targets.

Single versus bilateral lung transplantation in idiopathic pulmonary fibrosis: A systematic review and meta-analysis

Objective

Lung transplantation remains the only curative treatment for end-stage lung disease, conferring a better survival for some IPF patients, but whether they should receive double lung transplantation (DLT) or single lung transplantation (SLT) is still controversial. The aim of this study was to determine which type of lung transplantation was more effective and relatively safe in IPF patients by meta-analysis.

Methods

Publications comparing overall survival (OS) or other perioperative characteristics between IPF patients undergoing SLT and DLT were selected from electronic databases. The hazard ratios (HRs) were abstracted or calculated to evaluate the survival outcome. Odds ratios (ORs) or mean differences (MDs) were used to compare the causes of death or perioperative parameters. A random-effect model was used to combine data. Heterogeneity was quantified by means of an I² with 95% confidence interval (95% CI). The publication bias was estimated using the Eggers test with Begg’s funnel plots.

Results

16 studies with 17,872 IPF cases who met the inclusion criteria were included in this meta-analysis. SLT was associated with declined post-transplant FEV1% (MD = -15.37, 95% CI:-22.28,-8.47; P<0.001), FVC % (MD = -12.52, 95% CI:-19.45,-5.59; P<0.001) and DLCO% (MD = -13.85, 95% CI:-20.42,-7.29; P<0.001), but no significant advantage of DLT over SLT was seen in the overall survival outcome (HR = 1.08, 95% CI: 0.91–1.29; P = 0.391). Subgroup analyses for studies of follow-up period ≥ 60 months also showed similar results (all P-values>0.05). Moreover, there was fewer deaths attributable to primary graft dysfunction in SLT recipients (OR = 0.31, 95% CI: 0.2–0.48; P<0.001), while more patients with SLT died of malignancy (OR = 3.44, 95% CI: 2.06–5.77; P<0.001).

Conclusion

Our findings suggest that DLT was associated with better postoperative pulmonary function, but there was no difference in long-term overall survival between patients undergoing DLT and SLT. However, further high-quality and large-scale studies are needed to confirm these findings.

China lung transplantation developing: past, present and future

Lung transplantation in China has been developing for almost 40 years (1979-2019). The pioneers of this procedure experienced struggles and obstacles upon accomplishment of the initial 20 cases of lung transplantation. Like the expanding process of transplant programs elsewhere in western countries and other regions in Asia, transplant teams in China have found their own way to step forward, with the establishment of the two largest centers in Beijing and Wuxi. Since 2015, which was a novel start and milestone for transplant affairs in China, the pace of transplant volume and comparable quality of care for lung transplant recipients have increased noticeably. We reviewed the advancement of lung transplantation programs and registry setup in China and indicated that more socioeconomic factors and human care aspects needed to be considered to benefit Chinese recipients, which may further inspire the modification of criteria of listing and organ utilization based on East Asian cultural and traditional origins.

Single versus double lung transplantation for fibrotic disease-systematic review

Background

Lung transplantation has long been the accepted therapy for end-stage pulmonary fibrotic disease. Presently, there is an ongoing debate over whether single or bilateral transplantation is the most appropriate treatment for end-stage disease, with a paucity of high-quality evidence comparing the two approaches head-to-head.

Methods

This review was performed in accordance with PRISMA recommendations and guidance. Searches were performed on PubMed Central, Scopus and Medline from dates of database inception to September 2019. For the assessed papers, data was extracted from the reviewed text, tables and figures, by two independent authors. Estimated survival was analyzed using the Kaplan-Meier method for studies where time-to-event data was provided.

Results

Overall, 4,212 unique records were identified from the literature search. Following initial screening and the addition of reference list findings, 83 full-text articles were assessed for eligibility, of which 17 were included in the final analysis, with a total of 5,601 patients. Kaplan-Meier survival analysis illustrated improved survival in patients receiving bilateral lung transplantation (BLTx) than in those receiving unilateral transplantation for idiopathic pulmonary fibrosis at all time intervals, with aggregated survival for BLTx at 57%, 35.3% and 24% at 5-, 10- and 15-year follow-up, respectively. Survival rates for SLTx were 50%, 27.8% and 13.9%, respectively.

Conclusions

Whilst a number of studies present conflicting results with respect to short-term transplantation outcomes, BLTx confers improved long-term survival over SLTx, with large-scale registries supporting findings from single- and multi-center studies. Through an aggregation of published survival data, this meta-analysis identified improved survival in patients receiving BLTx versus SLTx at all time intervals.